In this in-class exercise, I will learn how to apply spatial point analysis techniques
The following five R Packages are used * sf is mainly used for importing geospatial data * Maptools is used to convert spatial object to ppp format (vector data conversion method) * All output of spatstat is going to be raster grid * sf is specially design for sf layr, raster is specially designed for raster layer
sg_sf <- st_read(dsn = "data/shapefile", layer = "CostalOutline")
Reading layer `CostalOutline' from data source
`C:\Niharika-avula\IS415_blog\_posts\2021-09-06-in-class-exercise-4\data\shapefile'
using driver `ESRI Shapefile'
Simple feature collection with 60 features and 4 fields
Geometry type: POLYGON
Dimension: XY
Bounding box: xmin: 2663.926 ymin: 16357.98 xmax: 56047.79 ymax: 50244.03
Projected CRS: SVY21
mpsz_sf <- st_read(dsn = "data/shapefile", layer = "MP14_SUBZONE_WEB_PL")
Reading layer `MP14_SUBZONE_WEB_PL' from data source
`C:\Niharika-avula\IS415_blog\_posts\2021-09-06-in-class-exercise-4\data\shapefile'
using driver `ESRI Shapefile'
Simple feature collection with 323 features and 15 fields
Geometry type: MULTIPOLYGON
Dimension: XY
Bounding box: xmin: 2667.538 ymin: 15748.72 xmax: 56396.44 ymax: 50256.33
Projected CRS: SVY21
childcare <- read_rds("data/rds/childcare.rds")
CHAS <- read_rds("data/rds/CHAS.rds")
CHAS_sf <- st_as_sf(CHAS,
coords = c("X_COORDINATE",
"Y_COORDINATE"),
crs = 3414)
childcare$Lat <- as.numeric(childcare$Lat)
childcare$Lng <- as.numeric(childcare$Lng)
childcare_sf <- st_as_sf(childcare,
coords = c("Lng",
"Lat"),
crs = 4326) %>%
st_transform(crs = 3414)
childcare <- as_Spatial(childcare_sf)
CHAS <- as_Spatial(CHAS_sf)
sg <- as_Spatial(sg_sf)
childcare_sp <- as(childcare, "SpatialPoints")
CHAS_sp <- as(CHAS, "SpatialPoints")
SG_sp <- as(sg, "SpatialPolygons")
childcare_ppp <- as(childcare_sp, "ppp")
CHAS_ppp <- as(CHAS_sp, "ppp")
tmap_mode ('view')
tm_shape(childcare_sf)+
tm_dots(alpha = 0.4,
col = "blue",
size = 0.05) +
tm_shape(CHAS_sf) +
tm_dots(alpha = 0.4,
col = "red",
size = 0.05)
tmap_mode('plot')